The Solar Impulse 2 takes off at airport in Abu Dhabi, at the start of an attempt to fly around the world in the solar-powered plane

The Solar Impulse 2 takes off at airport in Abu Dhabi, at the start of an attempt to fly around the world in the solar-powered plane

The Solar Impulse 2 takes off at Al Bateen airport in Abu Dhabi, at the start of an attempt to fly around the world in the solar-powered plane March 9, 2015. Two Swiss pilots, Bertrand Piccard and Andre Borschberg, on Monday embarked on the attempt to fly around the world on the solar-powered airplane that is expected to last for five months and is aimed at promoting clean technology in the aviation sector. On its five-month journey of 35,000 km (22,000 miles), the engines will be powered only by solar energy. REUTERS/Ahmed Jadallah (UNITED ARAB EMIRATES – Tags: TRANSPORT ENVIRONMENT ENERGY)